This invention relates generally to the field of mechanical fasteners for printed circuit board applications and, in particular, to a latching apparatus and method for providing radial alignment of a housing mounted on a printed circuit board.
Many types of electronic devices typically include conventional printed circuit boards. Oftentimes, connectors having plastic housings need to be mechanically fastened to the circuit board. Because the various connectors are oftentimes very small, and because of the limited space on the printed circuit board, the precise alignment of these plastic housings on the circuit board is oftentimes critical. Moreover, it is equally important that the housings be securely fastened to the circuit board so that the housings remain in place when subjected to lateral forces.
Conventional connector housings typically include one or more plastic snap leg latches that extend through openings in the circuit boards. The snap leg latches may include a head portion that engages the circuit board thereby securing the housing to the circuit board. Examples of such snap leg latches are shown in FIGS. 1 and 2 of Des. Pat. No. 278,143 (see also, U.S. Pat. Nos. 5,281,149, 5,255,159, and 6,058,579).
However, there are several disadvantages to these conventional snap leg latches. For example, when the snap leg latches are in the installed position, the cross section of the latches may only occupy approximately 60% of the receiving hole in the circuit board. The xe2x80x9copenxe2x80x9d space is typically required to provide the necessary clearance for the snap legs to enable the latch to operate. Because conventional snap leg latches typically occupy less than 100% of the volume of the receiving hole (see, for example, FIGS. 1 and 2 of Des. Pat. No. 278,143), they typically do not adequately prevent radial movement of the housing when lateral forces are applied to the housing. As a result, these conventional latches may result in the misalignment of connectors mounted on the circuit board.
Accordingly, it would be desirable to provide an apparatus and method of providing improved radial alignment of a housing mounted on a circuit board that overcomes the disadvantages described above.
One aspect of the invention provides a latching apparatus for providing radial alignment of a housing mounted on a circuit board. A mounting leg portion extends outward from a mounting surface of the housing. The mounting leg portion has a body portion, an end portion, and a radial alignment portion. The radial alignment portion extends outward from the mounting surface. The radial alignment portion has a circumference, and is adapted to be received in a mounting opening formed in the circuit board. The end portion of the mounting leg portion includes a snap portion for engaging the circuit board and securing the mounting leg portion to the circuit board. The radial alignment portion prevents radial movement of the mounting leg portion with respect to the circuit board. The circuit board may preferably include a first side and a back side, and the mounting surface of the housing may preferably contact the first side of the circuit board. The snap portion may preferably extend through the mounting opening. The snap portion may preferably include a flange portion for contacting the circuit board. The flange portion may preferably extend outward perpendicular to the body portion of the mounting leg portion. The mounting leg portion may preferably extend outward substantially perpendicular from the mounting surface of the housing. The body portion may preferably include a planar inner surface and a curved outer surface. The mounting leg portion may preferably be integrally formed with the housing. The mounting leg portion and the housing may each preferably be formed from plastic.
Another aspect of the invention provides a system for providing radial alignment including a housing mounted on a circuit board. The circuit board has a first side, a back side, and at least one mounting opening formed therein. The housing includes at least one mounting leg portion extending outward from a mounting surface of the housing. The at least one mounting leg portion has a body portion, an end portion, and a radial alignment portion. The radial alignment portion extends outward from the mounting surface. The radial alignment portion has a circumference. The radial alignment portion is received in the mounting opening. The end portion of the mounting leg portion includes a snap portion for engaging the circuit board and securing the mounting leg portion to the circuit board. The radial alignment portion prevents radial movement of the mounting leg portion with respect to the circuit board. The radial alignment portion may preferably be positioned between the first side of the circuit board and the back side of the circuit board. The mounting surface of the housing may preferably contact the first side of the circuit board. The snap portion may preferably extend through the mounting opening. The snap portion may preferably include a flange portion for contacting the circuit board. The flange portion may preferably contact the back side of the circuit board. The at least one mounting leg portion may be two mounting leg portions, and the at least one mounting opening may be two mounting openings.
Another aspect of the invention provides a method of providing radial alignment of a housing mounted on a circuit board. A mounting leg portion extends outward from a mounting surface of the housing. The mounting leg portion has a body portion, an end portion, and a radial alignment portion. The radial alignment portion extends outward from the mounting surface. The radial alignment portion has a circumference, and the circuit board has a mounting opening formed therein. The radial alignment portion is positioned into the mounting opening, and radial movement of the mounting leg portion with respect to the circuit board is prevented. The circuit board may preferably include a first side and a back side. The mounting surface of the housing may preferably be contacted against the first side of the circuit board. The radial alignment portion may preferably be positioned between the first side of the circuit board and the back side of the circuit board. The end portion of the mounting leg portion may preferably include a snap portion. The snap portion may preferably be contacted against the circuit board, and the mounting leg portion may preferably be secured to the circuit board. The snap portion may preferably extend through the mounting opening.
The invention provides the foregoing and other features, and the advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention and do not limit the scope of the invention, which is defined by the appended claims and equivalents thereof.